Cosmetic brush



FIG. 1 is a top perspective view of a cosmetic brush showing my new design;

FIG. 2 is a side view thereof;

FIG. 3 is an opposite side view thereof;

FIG. 4 is a rear view thereof;

FIG. 5 is a front view thereof;

FIG. 6 is a top view thereof; and,

FIG. 7 is a bottom view thereof. 

CLAIM The ornamental design for a cosmetic brush, as shown and described. 